308 BULLETIN OF THE BUREAU OF FISHERIES. 



CHARACTER OF OVARIAN EGGS. 



The ovaries are greatly distended just before spawning and appear as a bright red, 

 bilobed organ extending from the head beyond the cephalo thorax, the posterior end lying 

 between the muscles of the first segment of the abdomen. The ovary has a mealy appear- 

 ance when the eggs are fully developed, and it is very fragile. The eggs under the micro- 

 scope appear to be without a shell or other protecting covering, and they soon coagulate 

 in water, becoming white and opaque. The eggs are not round, but of various shapes, 

 due to being packed closely together in the ovary. Their greatest diameter, however, 

 is not more than 0.5 mm. The yolk material is very dense and granular, and the nucleus 

 of the cell is rather difficult to find. 



HABITS OF THE FEMALE DURING SPAWN BEARING. 



Spawn-bearing females in captivity seek sheltered places in the pens and are less 

 active than those not bearing spawn. It was observed that females bearing eggs about 

 to hatch were less active than those whose eggs were newly laid, and this was of con- 

 siderable aid in selecting individuals with ripe eggs for experiments in hatching. 



The female while carrying spawn normally assumes a resting position; that 

 is, it rests on the bottom on the tips of the dactyls with the tail somewhat extended and 

 the uropods curved downward. The exopodites of the pleopods beat slowly and rhythmi- 

 cally, evidently for the purpose of keeping the water about the eggs in circulation. 

 There are two movements of the pleopods which alternate at frequent but irregular 

 intervals. One movement is backward and forward at the rate of 55 or 60 times per 

 minute. The tail is slightly raised and the pleopods extended before the other move- 

 ment, which is more rapid, the pleopods beating obliquely 65 to 70 times per minute, 

 begins. The fifth legs are used frequently to manipulate the eggs and no doubt clean 

 away any sediment or debris that might settle on them. 



Small fishes sometimes attack spawn-bearing females, but they are often repulsed 

 with the antennae. There is little tendency for the female to move, and usually but little 

 food is taken when the eggs are about to hatch. 



TIME OF SPAWNING. 



There is no sharply defined spawning season, since spiny lobsters bearing spawn 

 have been found throughout all the year except during the winter. The maximum 

 number spawn in the spring and early summer, the first being females of large size. 

 Small females measuring 2^ to 3 inches, length of carapace, have been observed bearing 

 eggs late in the fall, but no spiny lobsters have been seen with spawn in November, 

 December, or January. It is known that spawn-bearing females are brought to market 

 later in the season from places west of Key West than from banks near Key West, and 

 that the earliest spiny lobsters observed with spawn come from places considerably east 

 of Key West. 



The time between successive spawning periods of individuals is not known, but it is 

 certain that spawning does not occur more than once a year. Females kept in pounds 

 did not spawn the second year of captivity, and but one out of over a hundred was 

 observed bearing a new seminal vesicle after molting during the second season. 



